Research on a Multimode Wideband Tonpilz Transducer

Tonpilz transducers are widely used for underwater application, and broad-band longitudinal transducers have very important applications, so that people adopt various kinds of methods to achieve its broadband projecting. Vibration components like spring ring and liquid cavity is introduced into traditional longitudinal transducers to implement multimode broadband longitudinal transducers which are able to stimulate the first and second order vibrates on longitudinal mode and liquid cavity vibration, which can achieve broadband projecting. The finite element model of transducer is set up with COMSOL software and the structure of the transducer is optimized．A final transducer based on the above research achieves the first longitudinal mode of 2.75kHz. The bandwidth of transducer is 2.5kHz-7kHz, in which the ripple of the transmitting voltage response does not exceed 4dB and the maximum of the transmitting voltage response is 143dB. The multimode broadband longitudinal vibration transducer developed in this paper is a sound source that can realize middle-low frequency, broad-band, high power transmission and deep-water work. The transducer achieves the projecting performance of middle-low frequency, broad-band, high power, which is a kind of good underwater source.